It is important to imagine this process as you breathe. Physically, some aspects may not be occurring but it is important to pretend until you understand.
Keep the mouth shut and breathe in through the nose. Breathe from the diaphragm and take the breathe deep into the bottom of the lungs, then the top of the lungs, and then fill the middle of the lungs. All this must be repeated for each single inward breathe.
Open the mouth to a small aperture and breathe out slowly. Exhale every last bit of air from the lungs before breathing in again. As you breathe out, imagine energy leaving the base of the stomach area and rising up your body. This energy can be sent to anywhere in your body and extended from your body. Use your mind to visualise the process and focus on where you want the energy to go.